@article { author = {Beheshti-Maal, Keivan and Shafiee, Noushin}, title = {A novel high ethanol-thermo-tolerant Acetobacter pasteurianus KBMNS-IAUF-2 strain and the optimization of acetic acid production using the Taguchi statistical method}, journal = {Microbiology, Metabolites and Biotechnology}, volume = {2}, number = {2}, pages = {77-88}, year = {2019}, publisher = {Iranian Research Organization for Science and Technology (IROST)}, issn = {2980-8855}, eissn = {2980-8855}, doi = {10.22104/armmt.2019.3633.1029}, abstract = {Because of the high energy consumption for fermentor cooling, the isolation of thermo-tolerant Acetobacter strains for vinegar production has a high priority. The aims of this study were the isolation and identification of a high ethanol-thermo-tolerant Acetobacter spp. from grapes as well as the optimization of conditions for increasing the acetic acid production. The grape extract was cultured on Frateur and Carr media. The isolates were characterized against macroscopic, microscopic, and molecular traits. The resistance of the isolates against different concentrations of ethanol as well as high temperatures were measured. The best ethanol- thermo-tolerant isolate using ribotyping was identified as Acetobacter pasteurianus KBMNS-IAUF-2 and its 16s-rDNA sequence was deposited in GenBank, NCBI under the accession number MG547344. This strain was able to grow in Carr medium with 9% (v/v) ethanol after 48h incubation at 40°C. A Taguchi design with L9 analysis revealed that the highest yield of acetic acid production occurred at 34°C in the medium containing of 2% (v/v) ethanol and 2% (w/v) yeast extract. The temperature and yeast extract concentration with 76.70% and 6.29% were the most and least effective factors in acetic acid production, respectively. The acetic acid production yield after 24h under the optimized condition was measured as 97%. This thermo-ethanol-tolerant strain could be applied as an industrial starter for producing vinegar with grapevine flavor.}, keywords = {acetic acid,Acetobacter pasteurianus,Ethanol,Taguchi Statistical Design,Thermo-Tolerant Acetic Acid Bacteria,Vinegar}, url = {https://armmt.irost.ir/article_879.html}, eprint = {https://armmt.irost.ir/article_879_7ff7ec976babb20ec60f4cb5dbddd049.pdf} } @article { author = {Borhani, Matia Sadat and Etemadifar, Zahra}, title = {Enhancement/evolution of biodesulfurization 4S pathway by genetic engineering and bioinformatic approaches}, journal = {Microbiology, Metabolites and Biotechnology}, volume = {2}, number = {2}, pages = {89-99}, year = {2019}, publisher = {Iranian Research Organization for Science and Technology (IROST)}, issn = {2980-8855}, eissn = {2980-8855}, doi = {10.22104/armmt.2020.3783.1034}, abstract = {Biodesulfurization could be a beneficial method in the industry for lowering the sulfur content of crude oil and could improve the efficiency of currently and costly used method, i.e., hydrodesulfurization. But, to achieve this goal, it is critical to enhancing the BDS rate using genetics and other omics approaches. The reason attributed to the fact that the desulfurization activity of currently available natural biocatalysts does not meet the needs of the petroleum industry. Based on the expression of the 4S pathway genes in several heterologous hosts with no ability of desulfurization, the involved genes are ideal targets for enhancement through genetics or metabolic engineering approaches. This review provides an overview of the reported solutions concerning identification of new desulfurizing genes and their regulation, elimination of the inhibitory effects of end products, solving the problem of mass transfer, increasing the production, specific activity, and stability of the involved enzymes, and enhancing the resistance of recombinant strains to the biodesulfurization conditions. Also, the results of some bioinformatics studies which can help in the genetic engineering of desulfurizing strains were provided. Overall, genetic engineering and bioinformatics techniques can be effective in solving the problems of the biodesulfurization process in the near future as a complementary method of hydrodesulfurization.}, keywords = {Biodesulfurization,4S Pathway,dsz genes,Genetic Engineering,Recombinant Strains}, url = {https://armmt.irost.ir/article_930.html}, eprint = {https://armmt.irost.ir/article_930_1cde6bc6786549ff4f936674e75847ac.pdf} } @article { author = {Sharifzadeh, Farzin and Dizajnejad, Golsa and Mohammadhassanpour, Selma and Rahnama, Nooshin}, title = {Cellulase production by Penicillium expansum MDFS2 during solid-state fermentation of rice straw, rice bran and wheat straw residues}, journal = {Microbiology, Metabolites and Biotechnology}, volume = {2}, number = {2}, pages = {101-108}, year = {2019}, publisher = {Iranian Research Organization for Science and Technology (IROST)}, issn = {2980-8855}, eissn = {2980-8855}, doi = {10.22104/armmt.2020.4326.1045}, abstract = {Production of fungal cellulase was performed by the isolate of Penicillium expansum MDFS2 on rice straw, rice bran, and wheat straw under solid-state fermentation. The greatest potential growth was detected using rice bran as the carbon source substrate. On the fifth day of fermentation, filter paperase, carboxymethyl cellulase, and β-glucosidase obtained their maximal activities of 4.91 U/g substrate, 36.51 U/g substrate, and 12.21 U/g substrate, respectively. The optimum temperature for filter paperase was reported at 40 °C, whereas carboxymethyl cellulase and β-glucosidase were optimally active at 50 °C. Filter paperase and carboxymethyl cellulase showed maximum activity at pH 5.0. However, β-glucosidase proved to be maximally active at pH 6.0. According to the thermal stability results, all the three components of the cellulolytic enzyme complex proved to be less thermally resistant at 60 °C, as compared to 50 °C. β-glucosidase and carboxymethyl cellulase depicted the highest and the lowest thermal resistance, respectively. β-glucosidase and filter paperase stored for one week at -20 °C proved to be the most and least stable enzymes, respectively. It is hoped that current research findings will help in the cost-effective production of industrially important cellulases using agro-industrial by-products as fermentation substrates.}, keywords = {Cellulase,‎ Agricultural waste,‎ Penicillium expansum ‎MDFS2,‎ Solid-state fermentation}, url = {https://armmt.irost.ir/article_1026.html}, eprint = {https://armmt.irost.ir/article_1026_70a0cfd6aabf2e04878ca97bc0a49773.pdf} } @article { author = {Shishavan, Mina and Mirdamadi, Saeed and Ofoghi, Hamideh}, title = {Antioxidant activity of alcalase hydrolysates of Spirulina proteins}, journal = {Microbiology, Metabolites and Biotechnology}, volume = {2}, number = {2}, pages = {109-118}, year = {2019}, publisher = {Iranian Research Organization for Science and Technology (IROST)}, issn = {2980-8855}, eissn = {2980-8855}, doi = {10.22104/armmt.2020.4280.1041}, abstract = {Spirulina microalgae are gaining increasing consideration for its pharmaceutical and nutritional (60–70% protein) virtues. Protein can be further processed to produce peptides that have functional and nutritional properties such as antihypertensive, immunomodulatory, antioxidant, hypocholesterolemic, and metal chelating activity.The purpose of this study is to investigate the relevance between antioxidant properties and the degree of hydrolysis (DH)of hydrolysates resulting from the effect of the alcalase enzyme on Spirulina protein at different times and the effect of time on the DH. For this purpose, Spirulina cells were disrupted with ultrasonication, bead milling, and water suspension methods. The resulting cell extract was hydrolyzed with serine proteases like the Alcalase enzyme. The sampling was taken every hour for up to 6 hours. DH of the samples was measured by the ortho-phthalaldehyde (OPA) method. Antioxidant activities of the hydrolysates were evaluated by assessing 2,2-diphenyl-1-picrylhydrazy (DPPH) and 2, 2′-azinobis (3-ethyl- benzothiazoline-6-sulphonate) (ABTS) radical scavenging activity. The ultrasonication method was selected for cell wall disruption. Results demonstrate that the highest increase in DH occurred in the first hour of hydrolysis. Then DH increased gradually with a low slope. The highest DH with an enzyme/substrate ratio of 1% (v/v) was 33.45% after 6 hours. Maximum DPPH radical scavenging activity occurred precisely at 120 minutes (22.71 ± 1.18 µM TE/mg protein, DH=28.29 ± 0.58). The scavenging activity of the DPPH radical increased by more than 2-fold after 2 hours of hydrolysis. The antioxidant activity of ABTS radicalscavenging increased and reached 862.09 ± 22.26 µM TE/mg protein after 5 hours of hydrolysis (DH%=32.83 ± 0.87). This research indicates that along with the increase of DH, the ABTS radical scavenging activity also increases. Therefore, hydrolysis produces peptides that can scavenge DPPH and ABTS radicals at certain times. These results can be used to determine both DH and the time it occurs; therefore, the probability creation and isolation of bioactive peptides increase with high antioxidant activities. So, the hydrolysates or peptides derivative from Spirulina can be used as a functional food to improve and even prevent various diseases and disorders.}, keywords = {Spirulina,cell disruption,degree of hydrolysis,Antioxidant activity,Alcalase}, url = {https://armmt.irost.ir/article_998.html}, eprint = {https://armmt.irost.ir/article_998_5b08d4470853297cdbd71fdf95fcc823.pdf} } @article { author = {Gholami, Dariush and Emruzi, Zeinab and Noori, Ali Reza and Aminzadeh, Saeed}, title = {Advances in bacterial identification and characterization: methods and applications}, journal = {Microbiology, Metabolites and Biotechnology}, volume = {2}, number = {2}, pages = {119-136}, year = {2019}, publisher = {Iranian Research Organization for Science and Technology (IROST)}, issn = {2980-8855}, eissn = {2980-8855}, doi = {10.22104/armmt.2020.4319.1044}, abstract = {Characterization and identification of bacteria and microorganisms are crucial in several fields such as medical, agricultural, and industrial microbiology. Conventional phenotype-based identification methods use low-precision scoring systems and therefore are affected by species phenotypic variations. These methods have low levels of reproducibility, which results in a decrease in the accuracy coefficient. Furthermore, conventional phenotype-based identification techniques include several methods, such as observation of growth and colony morphology, biochemical characterization, and conventional available biochemical methods, that are less accurate. Molecular-based methods have better strategies to identify and characterize microorganisms and bacteria. The development of molecular-based techniques has improved our ability to identify bacterial species in culture-dependent and culture-independent samples. Most of these techniques are only capable of identifying single bacterial strains or small groups of organisms at a time. However, some methods can be used to identify and characterize the bacterial communities in a range of hundreds to thousands of single strains. We also know that each of these methods has weaknesses and shortcomings that limit their application and usability. However, some of these methods have the strengths and potentials to improve conventional methods and to compensate for their shortcomings. In the present review, we highlighted recent progress in the field of bacterial characterization and identification using molecular-based techniques and discussed their abilities and limitations. }, keywords = {Bacterial identification,Molecular-based techniques,Phenotype-based identification methods}, url = {https://armmt.irost.ir/article_988.html}, eprint = {https://armmt.irost.ir/article_988_293b6a778e4e77fb30861a8c8b19ae2d.pdf} } @article { author = {Mohammadifar, Shamameh and Fallahi, Syamak and Asef Shayan, Mohammad Reza and Vaziri, Atousa}, title = {Antioxidant Activity and Some Biochemical Properties of Ganoderma applanatum (Pers.) Pat. from Iran}, journal = {Microbiology, Metabolites and Biotechnology}, volume = {2}, number = {2}, pages = {137-145}, year = {2019}, publisher = {Iranian Research Organization for Science and Technology (IROST)}, issn = {2980-8855}, eissn = {2980-8855}, doi = {10.22104/armmt.2021.4454.1047}, abstract = {Members of Ganoderma, belonging to Basidiomycota, such as Ganoderma applanatum (Pers.) Pat., have been recognized in traditional and modern medicine and pharmacology for their biochemical properties. In this study, first, the fruit bodies of G. applanatum growing on three tree species, Carpinus betulus L. (common hornbeam), Prunus cerasifera Ehrh. (cherry plum), and Prunus avium (L.) L. (sweet cherry), were collected in Neka, a county in Mazandaran Province in Iran. Then, their antioxidant activities were measured by the 1,2-diphenyl-2-pricrylhydrazyl (DPPH) radical scavenging method and the ferric reducing antioxidant power (FRAP) assay method, and their bioactive compounds contents were examined by a spectrophotometer and the HPLC method. The total phenols and flavonoids content and also antioxidant activity measured by the DPPH method in fungi growing on C. betulus were higher than the others. The fungi growing on P. cerasifera had the highest antioxidant activity examined by the FRAP method and the total polysaccharides content. Fungi growing on P. avium had the highest content of total proteins. Also, ursolic acid was not found in the samples, and betulinic acid was only seen in the samples growing on C. betulus. Oleanolic acid was not found in fungi growing on C. betulus and its amount in the fungi growing on P. cerasifera was higher than in samples growing on P. avium. }, keywords = {Ganoderma applanatum,Host plants,Biochemical properties}, url = {https://armmt.irost.ir/article_1027.html}, eprint = {https://armmt.irost.ir/article_1027_0825443503aea5e2b327e34bb22dc4bf.pdf} }